Steam-accumulator plant



Jan 3, 1928; v

v 1,654;955 w F. WETTSTEIN STEAM ACCUMULATOR PLANT Filed Nov. :50, 1925s Sheets-Sheet 1 Q/ 7 WA;

#ZdvATTORNEY I BY Jan. 3, 1928.

F. WETTSTEIN STEAM ACCUMULATOR PLANT ed Nov. so, 1925 SSh'eets-Sheet "2Comps/v.95?

firm/Mira INVENTOR' Pum a, ATTORNEY Jan. 3,1928, 1,654,955 F. WETTSTEINv STEAM ACCUMULATOR PLANT Filed Nov; 30, 1925 s Sheets-Sheet s INVENTOR;

agd/mw 4&ATT0R EY Patented Jan. 3, T928.-

UNITED STATES'PATENT'OF'FICE.

rn'Irz wnrrsrnm,'-or SUMMIT, vnwunnsnv, ASSiGNdR To BUT-HS AccnmULA'ron.eomrany, me, on NEW YORK, 1v. Y., A conrormrron or DELAWARE.

" sm AM-AoouMULA'ron PLANT. 4

My invention relates to steam plants and 1 more particularly to plantswhere steam of high temperature is generated and in which-.-

storage of steam takes place so that the boilers may be operatedindependently of steam demand. I

The tendency in steam generation 1s toward higher temperatures andhigher pressures. Steam boilers .can be built ofany desired pressure'hyuse of boiler tubes of small diameter-but the nature of material used inboiler construction .is such that there is a limit of temperature abovewhich it is not possible to generate steam.

According to the laws of thermo dynamics, the Carnot-cycle is the mosteflicient cycle for thetransformation of heat energy into mechanicalenergy. The etficiency of this cycle ishigher, the higher thetemperature is, at which heat is introduced into the cycle, and thelower the temperature is,

at which heat is taken off. The. lower temperature is, determined by theprevailing temperatureof the atmosphere' It therefore becomes. evidentthat, in order to increase the efliciency of the Carnot-cycle, the

upper value of temperature must be in creased. This holds good also forother cycles such as the Rankine-cycle because all of these cycles canbe considered as the sum of infinitesimal Carnot-cycles. An arrangementwhich makes possible a definite and reliable control of the upper valueof temperature of a cycle, and which thus elimi nates danger or preventsinjury to materials which would result from excessive temperatures, istherefore highly desirable.

My invention provides such an arrange ment and includes means formaintaining temperature within any desired'limits while providingaccumulation of. steam so that the plant may vrun with high eificiency.In certain cases I generate steam of conditions where pressure andtemperature do not correspond. Pressure and temperature of steam have adefinite relation to each other -only within the range of saturatedsteam.

For superheated steam, for hot water under pressure and for the rangeabove critical pressure and temperature, where water and steam aregradually transformed into each other with no -definite line ofseparation between the two conditions, there exists no such definiterelation between pressure andtemperature. It, therefore, onlythepressure of steam is regulated, as'has been customary hitherto, adefinite temperature is obtained within the range of saturated steamonly, whereas, in the field oi hot water under pressure and ofsuperheated steam, the temperature may deviate considerably from thedesired or permissible value. With pressure control it is therefore notpossible to control, for example, the generation of steam in such a Waythat-a-constant temperature is maintained in the various ranges of hotwater under pressure, saturated steam and superheated steam, as isdesirable with certa n processes, such as, for example, the Carnotprocess. With temperature regulation however, as embodied in the presentinvention, the desired temperature may be maintained under allconditions, so that steam generation, for example, may take place closeto the maximum temperature whichthe steam stand. 1

The invention .Wlll be readily understood by reference to theaccompanying drawings generating apparatus will within which: Fig. 1shows diagrammatically 'apower plant according to my invention; Fig.

2 is a diagrammatic illustration of the man- '9 nor of controlling theflow oii'steam to the low pressure section of the turbine illus tratedin Fig. 1; Fig. 3 is a more or less diagrammatic showing of the controlmechanism for the supply of steam to the turbine of Fig. 1; Fig. l showsa second form of plant constructed and arranged according to theinvention; and Fig. 5 shows a according to the invention. I

' In Fig. 1, steam of high pressure and high temperature is generated inboiler 10 which may be of any type and which third plant may be fired inany desired way. The pres-- sure may be, for example, 4,000 lbs. per sq.in. and the temperature may be. 800 F. It is to be understood, however,that I do not limit myself to any values oft pressure and temperature.The pressure 13 maintained constant by means ot a reducing valve 11 inthe boiler supply conduit 12. any of various known types of reducingvalve may be use-r.-. For sake of illustration, 1 have shown i of How,valve 11 closes somewhat so that the pressure is reduced and, by suchmeans, the pressure is maintained constant. l

The steam generated which normally superheated steam passes throi ahconduit 16 to a motor 17, in the present instance, a turbine. Theturbine is of the condei'ising type havinga condenser 18. it is showndriving a load 19 consisting of an electric generator. The turbine hasan extraction conduit 20 connected thereto to eed steam from betweenstages. Steam bled through extraction conduit 20 passes through asuperhea't accumulator 21 containing any kind of material suitable"Eorthe storage of heat such as brick or metal and thence throughconduit 22 and charge conduit 23 afi'ord accumulation to the extentdesired.

Should the load on the turbine increase to such an extent that moresteainis required than is for the moment generated in the boiler, steamcan pass from the accumulator through conduit 22, through superheataccumulator 21 and-to the low pressure stages of the turbine. Steam mayalso be extracted from the accumulator through conduit 27. Steamcondensate formed in condenser 18 is pumped by pump 28 to conduit 29 andinto storage tank 80. 31 designates a malre-up line for the plant. Fromthe storage tank water is' drawn through conduit 32 by pump 33 and isforced by the pump into supply conduit 12. Pump 33 may be of any ofvarious types and may be driven in any desired manner. For the sake ofillustration, a centrifugal pump is shown driven by an electric motor34;. If desired the speed of the pump may be controlled but the pump canbe driven at constant speed with the reducing valve 11 serving as theonly regulating means. Any form of pump arrangement and pump control maybe used but an arrangement should preferably be selected which maintainsa constant supply pressure for the boiler. Supply of steam to turbine 17is controlled by temperature in supply conduit 16 in such a manner thatthe temperature in conduit 16 is maintained constant. Proton ably, theturbine is controlled ly what is ucn is the case the control 0'. supply01 known as mechanism of the, type indicated in 8.

In Fig. 3, 16 is the steam supply lineto the turbine. From conduit 16steam passes into distributing chamber217 to which is connected a seriesor passages 218 leading to a series of nozzles 219 which direct steaminto the passages of the first turbine wheel 20. Flow through passages218 is controlled by means of a mechanism operated to successivelyconnect said passages with distributinc chamber 21?. in the or ii shown,which to be understood as d1 amniatic to a considerable extent, this isaccomplished by means of a piston 221 slidahlc in the distributingchamber .217. The arrangen'ient is such that as piston 221 movesdownwardly closes oil the passages 218 one att r the the other insuccession thereby changing of steam how to the urbine. This regulationis "on tble because supply of steam o' nigh pressure no without any.opreciable loss in hi i Any type or thermostatic regulation nay controlthe mechanism "for changing the cross-sectional area of flow of steam tothe turbine. @ne term of mechanism is diagrammatically illust ated in 3comprising a thern'iostatic bulb 222 situated in conduit 16 and actedupon by the super-heated steam passing through conduit ltlfrom theboiler and co iected by means of a tube 223 to a diaphragm housing 224-.Housing 2261 has attached thereto on one side a diaphragm 225 andcontains a diaphragm chamber 326. Bulb 222, tube and cham her 326contain an expansible or volatile fluid, preferably a liquid, which uponincrease of temperature in conduit 16 expands, causing diaphragm 225 tolex upwardly as shown in Fig. 3. Movement of diaphragu'i 225 causeschange of liquid pressure on the upper side of piston 226 as follows:

A. fluid such as oil is supplied throughconduit 227 and enters chamber228 on the upper side of'piston 226 from which it passes out throughconduit 229. Conduit 229 is connected to a housing 2210 which has anoutflow opening 281 in the same, which opening is controlled by abatlling member movable across the opci'iing. Battling member 232 isformed on one end of a lever233 which is pivoted on a knife edge pivotat one end, indicated at 234. Movement of diaphragm 225 is transmittedto lever 233 through pin 235 and opposed to the pressure exerted on thevlcverby the diaphragm is a spring 236 which-rests between the lever anda lixed stud 237 which is arranged to be adjusted.

Opposed to the liquid pressure in chamber 228 is a spring 238. may becalled a servo-motor; parts 230, 231,

team to the turbine may be effected by Parts 226, 228 and. 238

expands causing an increase of pressure in chamber 326, whereupondiaphragm 225 is flexed upwardly. This causes-a clockwise movement oflever 233 as shown, as a result of which bafiiing member 232 is causedto increase the flow through outlet 231 by uncovering the outlet to agreater extent. Increased outflow through outlet 231 results in decreaseof pressure in chamben'228 whereupon piston 226 is moved upwardly underthe preponderating force of spring- 238. As a result, piston 221 is alsomoved upwardly thus connecting some of the passages 218 withdistributing chamber 217 so that more steam can .flow to the. turbine.This results'in a decrease of'temperature in conduit 16 since the flowof steam through the boiler is then at a greater rate and less heat isabsorbed per .pound of steam.

Suppose on the other hand, that the .temperature in conduit 16decreases. The fluid in bulb 222 then contracts and diaphragm 225- movesdownwardly whereupon the out flow through outlet 231 is restricted.This. causes an increase of pressure in chamber 230, conduit 229 andchamber228 causing a downward movement of piston 226 and a closing of agreater or lessnumber of passages 218 whereby supply of steam to theturbine is decreased and the temperature rises to normal Value.

Flow of steam to the low pressure section of the turbine is controlledby a speed responsive governor controlling entrance to the stages justbeyond extraction conduit 20. This speed'responsive governor is arrangedso that it tends to maintai'na constant tur= bine speed. For sake ofillustration, a diagrammatic view of this matter is presented in Fig. 2,although such regulation is known in the art. In Fig. 2, 39 designatesthe supply conduit to thelow pressure stages of the turbinebeyond'extraction conduit 20. This conduit is controlled by a valve 40which in turn is controlled by a centrifugal governor 41 operated fromoff the shaft of the turbine. The operation is such that when the speedof the turbine increases, centrifugal governor 41 acts to close valve 40more or less and conversely, it the speed of the turbine decreases, thegovernor opens the valve more or less.

In Fig. 1 is shown a by-pass line 42 between supply conduit 16 andextraction conduit 20. This by-pass line contains a valve 43 operated bya thermostat 44 in front of the same, that is, on the side nearest thesupply conduit 16. Expansion or contraction of fluid in thermostat-44acts through conduit 45 on a diaphragm 46 so that upon increase oftemperature the valve. tends to open. This valve is normally out ofoperation but comes into operation in case the temperature control forthe high pressure section of the turbine should fail to admit sufficientsteam to the turbine, or if the turbine cannot take more steam so thatthe temperature in con duit 16 should rise above the value normallymaintained by the temperature control of the turbine.

In'Fig. 4 is shown a plant more or less similar to that shown in Fig. 1except that; the steam passing through the accumulator does not firstpass through a motor. In this case the motor is controlled by acentrifugat the valve opens. .For sake of illustration there is shown abulb 50 in conduit 16 connected by means of tube 51 with a pistonchamber 52. Upon increaseof temperature in conduit 16, fluid expands inparts 50,51

and 52 causing a movement to the left.

shown, of piston 53- against the action of spring 54 therebyopeningvalve 49 to the re quired amount to cause the 'temperature to decreaseto normal value. In the plant shown in Fig. 4, the accumulator isadapted to supply steam through" conduit 55 to con-v sumers 57.Supply'of steam from the accumulator to conduit is controlled by a--reducing valve 56 which may beof any known type. The boiler in thiscase is shown as-comprised of a series of zigzag pipes. 'Obviously anynumber of types or boiler may be used within the scope of the invention.y

In the embodiment shown in Fig. 5 steam generated in boiler 60 passesinto conduit 61 from which two conduits branch off in parallel. one, 63,leading to turbine 62 and the second, 64, leading to the accumulator 65.Flow of steam into turbine 62 from conduit 63 is controlled by a seriesof valves '66, 67, 68 and 69 which are adjusted to open successively inthe order mentioned. Each of these valves is attached to a valve stemand each valve stem is attached to a motor. The motors for valves 66, 6768 and 69 are numbered 70, 71, 72, and '7 3 respectively and Actingdifferent strength, spring 78 being the weakest and spring 81 being thestrongest. @bviously valves 86 and 67 with their relative operations maybe interchanged since they control supply of steam to the same wheel125. Pipe 83 is open at. the point 80 and the opening thereof iscontrolled by a batfiing member 8? is moved by diaphragm 92 in conduit83, and consequently in coi'idu' comprising one side of a housing 93which is connected by means of conduits 94 and with athermostatic bulb96. also conduits 9-1 and 95 and the inner space of housing 93 containan expansible fluid, preferably a volatile liquid.

Consideringthe' parts thus far described without reference to othercooperative parts,

the operation is follows: Upon a slight increase in temperature inconduit 61 the fluid in bulb 96 expands and there results an increase ofpressure on diaphragm 92 which serves to decrease the outflow of oilthrough opening 80. The pressure in conduit 83 is thus increased andassumingl at lirst that all of the valves 66, 67, 68 and 69 are closed,the first effect will be to overcome the res ance of the weakest spring78 whereupon piston 71 will be moved to open valve 60. Upon furtherincrease 01 pressure in conduit "3 and connecting conduits, piston 75will be moved to open valve 67. Upon further in crease of pressure inconduit 83 result of continuing high temperature in conduit 01, valve68. controlling supply oiisteam to the second wheel 97' of the turbine,is opened. and upon still further increase of pressure 84 and 85, valve69 controlling supply or steam to the turbine stage 98 is, opened. Thereverse operation due to decrease of temperature in conduit 61 will bereadily understood :t'rom the above description.

The valves above described are controlled not alone by temperature ofsteam but also by the speed of rotation of turbine through the agency ofthe following apparatus: Conduit 100 has an opening 102 in the samewhich is controlled by a ball'hng member 103. Bal'l'ling member 103 iscontrolled by a centrifugal governor 104: comprising balls pivoted toswing outwardly upon increase of centrifugal effect due to an increaseof speed and connections with ballling member 103 to move the same awayfrom opening 102 upon increase of speed. The centrit ugal governor isshown diagrammatically as operated from the turbine shaft 105 by meansof bevel gears 106. Oil spraying out of opening 102 collectsinreceptacle 10? and This bulb and is conveyed back into 90 by means 01? iconduits 10S and 89.

Steam passes from. accumulator 65 through conduit 109 and conduit 01-into housing 110 which contains two valves 111 and 112 controllingsupply of steam to two oi? the lower pressure stages of the turbine butnot by delivery to the same stage; that is, valve 111 delivers to a lowpressure sta e 118 and valve 112 delivers steam to a still lower stage11 1-. These valves 111 and 112 are controlled by pistons 115 and 116respectively which are acted upoirby pressure of oil conveyed throughconduits 117 and 118. Opposed to the oil pressure are springs 119 and120 of whichspring 119 is the weaker so that valve 111 operates ahead ofvalve 112 upon increase ot pressure in conduit 117. The purpose of thisarrangement is to admit accumulator steam first to the higher pressurestage on discharge of the accumulator and conduit which is alsocontrolled by bailling member The action of valves 110 and 111 under theinfluence or the centrifugal governor is as follows: Suppose the speeddecreases to the point at which spring 119 is adjusted to yield. Thenballling member 103 throttles the outflow 01" oil through 123 to such anextent that oil pressure in conduit 117 is increased to overcome spring119 whereupon valve 111 is unseated and steam passes from accumulator65, through conduits 109 and 0-1, through alve 111 and to stage 113.Upon further decrease of speed, oil pressure in conduits 11? and 118rises so that valve 112 is opened. It is desirable that when valve 112opens, that valve 111 shall immediately shut. This may be done as shownon the drawing by causing a valve 126 operatively connected to piston116 to provide passage of motive fluid from conduit 117 to the springside of piston 115 so that the oil pressures are equalized to someextent and spring 119 preponderates. Upon reclosing of valve 112, valve126 connects the spring side of piston 115 withan outflow conduit 1 10.

To complete the regulation there is arranged in conduit 61 a temperaturecontrolled valve 128 operated by piston 129 on the one side of which oilpressure acts, the oil 1 being supplied through conduits 130 and 13messes The action of the complete regulation may .be described asfollows: Assumethat each of valves 66 and 67 are open but that valves 68and 69, 111' and 112 are closed. Now assume that the temperature risesinconduit 61. Rise of temperature in conduit 61 causes an expansion offluid in bulb 96, con- 85. This will have no effect on valves 66,

duits 95 and 94 and housing 93, whereby opening 86 is restricted andthere is an in creasein pressurain conduits 82, 83, 84 and to increasein supply of steam, the speed of turbine increases. Centrifugal governorat which opening 86 was throttled.

104 then raises baffling member 103 to increase the outflow of liquidthrough opening 102 and consequently there is a decrease of pressure inconduits 100, 101, 82, 83, 84

and 85, the result of which is a closing of some or all of valvescontrolling admission to stages. 12,5, 97 and 98. These valves willclose in succession, valve 69 closing first; then valve 68 then valve67, and, last, valve 66. Suppose that the increase of speed and theconsequent closing of one or more of the control valves for the hightemperature steam causes an increase of temperature in conduit 61 higherthan g at 1aphragm 136 is then moved to restrict opening134 whereuponpressure in conduit 130 and on piston 129 increases so that valve 128 isopened and steam is by-passed through conduit 64, through check valve129 and into the water space of the accumulator 65.

Assume onthe other hand, that the temperature in conduit 61 drops.Bafiiing member 135 is first caused to recede from opening 134 as aresult of which valve 128 becomes closed, thus cuttin off the supply tothe accumulator and irecting all the steam to the turbine. The effect ofthrottling of opening 86 before opening 134 can be effected in thestiftness'of diaphragms 92 and 136, or may be effected by other means.

' On further drop of temperaturethe outflow all these valves, lastmentioned, being open, .the speed is not up to normal.

Centrifugal governor 104 then operates to decrease the outflow throughopening, 123. This causes a rise of pressure in conduit 117 which riseof pressureacts on piston 115 to open valve 111. Steam then flows fromaccumulator further decrease of speed the consequent rise of pressure inconduits 117 and 118 piston 116 is operated to open valve 112- and steamthen flows from the accumulator to the interstage chamber ahead of stage114.

In this modification, as in those previously described, I prefertolcontrol the supply of feed .water to the boiler 60 by means of aabove disclosure without departing from the spirit and scope of theinvention.

Having thus described my invention, what I claim is:

' 1. A high pressure boiler, an accumulator,

a passage for superheated steamfrom said boiler to said accumulator, andautomatic temperature responsive valve mechanism to simultaneouslymaintain a constant temperature in said boiler and to control flow ofsuperheated steam through said passage.

2. In a steam plant, in combination, a high pressure boiler adapted toproduce superheated steam, an accumulator, a conduit for conductingsuperheated steam from said boiler toward said accumulato a valve insaid conduit, and temperatur responsive means to operate'said valve toincrease the flowof steam through said "valve upon increase oftemperature in said boiler and decrease the flow of steam through saidvalve upon decrease of temperature in said boiler.

3. In a steam plant, in combination, a boiler, an accumulator, a conduitfor passage of steam from said boiler to said accumulator, a maincontrol memberin said conduit to control flow of steam from said boilerto said accumulator, a liquid pressure operated V servo-motor to controlsaid main control member, a relay to control said servo-motor, saidrelay COIIIPI'lSlDg' a member. having an outlet therein for the outflowof a liquid- .and means to control the outflow of liquid through saidoutlet, and a thermostat to operate said relay to increase the flow ofsteam through said conduit upon increase of temperature in, said"conduit ahead of said" main control member and decrease the flowthrough said conduit upon decrease of temperature in said conduit aheadof said main control member.

4. In a steam plant, in combination, a steam boiler, means to supplyfeed water to said boiler, means to maintain the pressure of said. waterconstant, an accumulator, a

passage for steam from sai'dboiler tosaid accumulator, and meansresponsive to the temperature of steam leaving said boiler to controlflow of steam from said boiler to said accumulator.

5.' In a steam plant, in combination, a boiler, an accumulator, apassage for steam from said boiler to said accumulator, temperatureresponsive means to control flow through said passage to maintain aconstant temperature of steam in said boiler, and pressure operatedmeans operating to main tain a constant pressure in said boiler.

6. In a steam plant, in combination, a boiler, a feed Water supplyconduit for said boiler, a reducing valve in said feed Water supplyconduit, a steam supply pipe for said boiler and temperature responsivemeans in said steam supply pipe operating to main tain a constanttemperature in said boiler.

7. Method of producing and dispensing steam in a steam plant whichcomprises raising a body of water to a given pressure, applying heat tosaid body of Water to transform the same into steam at a rate'diflerentthan the rate of steam demand, with drawing steam at a rate such thatthe temperature of steam generated. is maintained constant, accumulatingsteam in amounts equal to the difference between steam withdrawal andsteam demand and utilizing the steam accumulated when the demand forsteam is greater than the rate of steam Withdrawal.

'8. In a steam plant, in combination, a source of superheated steam, anaccumulator, a passage for superheated steam from said source to saidaccumulator and a thermostat controlled valve in said passage operatingto maintain a constant temperature in the source.

9. In the steam plant, in combination, a source of steam, amotorsupplied with steam from said source, a plurality of valves controllingadmission of steam to said motor, and means responsive to temperature insaid source to operate said valves successively to maintain saidtemperature constant.

10. lln a steam plant, in combination, a source of steam, a motorsupplied from said source, an accumulator supplied with steamfrom saidsource, means to conduct steam from said accumulator to said motor, aplurality of valves controlling admission of steam to said motor, meansresponsive to temperature in said source to operate said valvessuccessively to maintain said temperature constant and meansto controlflow of steam from said accumulator to said motor.

11. In a steam plant, in combination, a steam boiler, a feed Watersupply conduit for said boiler, means to maintain the pressure in saidfeed Water supply conduit and said boiler constant, a motor, means toconduct steam from said boiler to said motor, and means responsive tothe temperature of steam leaving said boiler to control fiOW of steamfrom said boiler to said motor.

12. In a steam. plant, in combii steam boiler, a -.eed Water supply con:lit for said boiler,

a reducing valve in said teed reassess Water supply conduit,- a-motor,means to conduct steam from said boiler to said motor, and meansresponsive to the temperature of steam generated in said boiler tocontrol flow of steam to said motor.

13. In a steam plant, in combination, a source of high temperaturesteam, a motor including high pressure stages and low pressure stagessupplied from said source, a plurality ot valves controlling admissionof steam to said high pressure stages, means rcsponsive to temperaturein said source to close said valves successively upon drop oftemperature, a source of 10W pressure steam, means to conduct steam fromthe last men tioned source to said low pressure stages, a pluralityofvalves controlling admission of steam to said low pressure stages andmeans to open the last mentioned valves successively upon decrease ofspeed of said motor.

14. In a steam plant, in combination, a source of high temperaturesteam, a motor including high pressure stages and low pressure stagessupplied from said source, a plurality of valves controlling admissionof steam to said high pressure stages, means responsive to temperaturein said source to close said valves successively upon drop oftemperature. an a(.'ciunulator, means to conduct steam from said sourceto said accumulator, means to conduct steam from said ac cumulator tosaid low pressure stages, a plura-lity of valves controlling admissionof steam to said low pressure stages and means to open the lastmentioned valves successively upon decrease of speed of said motor.

15. In a steam plant, in combination, a motor having a plurality ofstages, an ac cumulator, means to conduct steam from said accumulator toseveral of the motor stages of dill'erent pressures, s iarate valvemechanisms to control admissn to the difi ercnt stages and means toclose a valve mechanism for a given stage when a valve mechanism for alowerpressure stage opens,

ltl-ln a steam plant, in combination, a boiler adapted to produce steamof unrelated temperatureand pressure conditions, an ac cumulator, aconduit for conducting said steam from said boiler toward said accumulater, a valve in said conduit and temperaturc responsive means tooperate said valve to increase the flow of steam through said -valveupon increase of the temperature of said steam and to decrease the tloivof steam through said valve upon decrease of temperature of said steam.

In testimony whereof I have atlixed my signature.

